This Balboa HydroAir extended wall fitting is well-suited to thick-walled spas (up to 50 mm), such as wooden hot tubs.

If your wall thickness is less than 35 mm, do not forget to add a nut with one of the adapters (straight nut for 50 mm pipe, 90° nut for a 1.5-inch pipe, 90° nut for a 50 mm pipe)

The female thread on the adapter is not long enough to crimp the part against the wall.

For shells that are less than 15 mm thick, use the short-threaded wall fitting instead.